1. Field of the Invention
This invention relates to tools and methods for accessing and deaccessing a medical device implanted under the skin of a patient, and particularly tools and methods which reduce the risk of a nurse accidentally sticking herself or himself or a patient with a needle.
2. Background Discussion
Implanted medical devices, such as vascular access devices, are commonly used to allow medication to be administered to patients. One such implant device is sold under the trademark xe2x80x9cBardPortxe2x80x9d by C. R. Bard, Inc. These devices include a housing enclosing a chamber which has an inlet covered with a silicone or latex seal. An outlet in communication with the chamber allows fluid in the chamber to flow through the outlet into a tube which, typically, is inserted into the vein of a patient.
These devices are accessed periodically by a nurse who inserts a needle through the patient""s skin overlying the device and then into and through the seal. The nurse palpates, or feels, the device through the skin overlying the implanted device, and presses downward to locate the position of the implanted device. While holding or pressing against the device through the skin with one hand, the nurse with the other hand inserts the needle through the skin, and into and through the seal. Once properly inserted through the skin, the tip of the needle penetrates the seal and is lodged within the chamber. A xe2x80x9cclickxe2x80x9d sound can sometimes be heard when the tip of the needle touches the bottom of the chamber, or the nurse can feel the tip contact the bottom of the chamber. Typically, the needle penetrates a depth of from about xc2xc inch to about 1 inch. Medication now flows through the needle into the chamber and then out the outlet through the tube into the vein of the patient. Sometimes, however, the nurse, while attempting to introduce the needle into the seal of the implanted device, accidently sticks herself or himself with the needle. These accidental needle sticks occur while either accessing or deaccessing the implanted device with the needle.
Needle sticks occur most frequently while deaccessing the needle. The needle sometimes remains in the implanted medical device for several hours, and sometimes even for several days.
These needles must be periodically flushed and removed from the device. The removal is accomplished by the nurse, with one hand, pressing against the skin overlying and around the device, and, with the other hand, grasping the needle and withdrawing it from the device. Frequently, there is an involuntary muscular recoil as the needle escapes from the implanted medical device as it is withdrawn. It is thought that this recoil is due to proprioceptive neuro-muscular activity. The recoil sometimes results in the nurse accidentally sticking a finger of the hand which is pressing against the skin adjacent to the implanted medical device. If the source patient has an infectious and or contagious disease such as disseminated TB, Hepatitis B or C, or is HIV positive or has AIDS, the nurse may contract the disease directly from this needle stick.
After such a needlestick, even if the source patient has no communicable and/or infectious disease or condition identified at the time of the needlestick, the nurse must undergo intensive and expensive follow-up testing intermittently for up to 1 year. The source patient must be tested, if they consent, for infectious or communicable disease as set forth in the OSHA regulations and CDC (Center for Disease Control) recommendations, under Employee Exposure to Bloodborne Pathogens. The nurse must also be counseled as to certain restrictions in his or her own lifestyle, particularly sex practices, until his or her own freedom from communicable/infectious disease or condition is determined. This places an incredible strain on the nurse""s marital relationships and lifestyle. The partner often demands that the nurse quit nursing rather than face the risks.
Needle sticks also occur while accessing the implanted device. The problem of contracting an infectious, contagious disease also is sometimes encountered. For example, the needle, which is typically sterile initially, has in some reported instances completely penetrated the finger of the nurse and entered the body of the patient. The now contaminated needle can only be removed by withdrawing it from the patient""s body into and through the nurse""s finger, possibly infecting the nurse.
Recent guidelines promulgated by the CDC prohibits medical acts which require manipulating needles using both hands in the act, or any other technique that involves directing the point of a needle toward any part of the health care workers body. Under the current protocols for using the implanted device, the nurse""s hand which secures the implanted device in place during accessing and deaccessing is always in direct line with the needle during accessing, and also in line with the needle tip during deaccessing when one considers the frequency of the known recoil phenomenon.
The problem of needle sticks while deaccessing the needle has been recognized by workers at the University Hospital in Antwerp, Belgium, who published an article in Infection Control and Hospital Epidemiology, Volume 14, No. 10 (October 1993). In this article it is suggested to use a tool, rather than the nurse""s hand, to hold the implanted device during removal of the needle. The suggested tool includes a guard with a slot in it. The guard has a relatively small area. It appears to be less than 1 square inch, and it appears to be made of an opaque material. There is a short handle attached to the guard used to grasp the tool which does not permit the hand of the nurse to be located far enough away from the needle to insure avoiding needle sticks if a recoil occurs.
It is the objective of this invention to provide tools and methods which allow a nurse to access and deaccess safely a needle used with an implanted medical device. This invention has several features, no single one of which is solely responsible for its desirable attributes. Without limiting the scope of this invention as expressed by the claims which follow, its more prominent features will now be discussed briefly. After considering this discussion, and particularly after reading the section entitled, xe2x80x9cDETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS,xe2x80x9d one will understand how the features of this invention provide its benefits, which include low cost manufacture, simplicity of use, and, most importantly, nurse and patient safety by avoiding accidental needle sticks and the ensuing medical costs and risks such as, for example, loss of health or life, ability to work, and sometimes spousal support.
The first feature of the tool of this invention is that it may be used for assisting in both accessing and deaccessing a needle used with a medical device implanted under the skin of a patient. In one embodiment it has the general configuration of a spatula and it includes an elongated body having a handle section and an enlarged guard section. There is an elongated slot extending from an edge of the guard section into the guard section, terminating at an internal portion of the guard section. The guard section has an area of 1.00 square inch or more, typically the area is from about 1.00 square inch to about 18 square inches. This relatively large guard area prevents the patient from being stuck with the needle, if there is a recoil during removal of the needle from the implanted medical device.
The second feature is the dimensions and other physical characteristics of the guard section. The guard section has a forward edge terminating at opposed ends and side edges at each opposed end which extend rearward to the handle section. The guard section has a floor including the forward edge, opposed sides, and a rear end. There is a raised rear wall connected to the rear of end of the floor, and a pair of raised side walls, each connected to one side of the floor. Preferably, the side walls taper down from their highest distance above the floor near the rear end to essentially level with the floor near the forward edge. The forward edge has a length of from about 1 to about 6 inches. The side edges have a length of from about 0.5 to about 3 inches. The guard section has a smooth, generally planar underside surface and a thickness of from {fraction (1/32)} to {fraction (3/16)} inch. The walls have a maximum height of about xc2xc inch.
The third feature is the dimensions and other physical characteristics of the slot. The slot extends from an edge of the guard section inward a distance in excess of xc2xc inch, preferably having a length of from about 0.25 to about 3 inches, and it has a width that is slightly broader than the diameter of the needle, typically from about {fraction (1/16)} to about xc2xc inch. Preferably, the slot is at a right angle with respect to the forward edge, and the slot and the handle section are in substantial alignment with each other, both lying along a common longitudinal axis. Preferably, the minimum distance between the slot and a side edge is about {fraction (3/16)} inch and the maximum distance between the slot and a side edge is about 3 inches. The elongated slot preferably has tapered edges. These tapered edges assist in removal of the needle from the implanted medical device.
The fourth feature is that the guard section is made of a transparent material. In most instances the entire tool is injected molded from a polymeric material such as, for example, polypropylene homopolymer or a polycarbonate, sold under the trademark LEXAN by General Electric, Inc. Because the guard section is transparent, the nurse may more easily align the tool with the implanted medical device. This is especially advantageous during accessing the implanted device. In one embodiment especially designed to assist in accessing the implanted device, the slot has along it""s length an enlarged open portion with an area in excess of 0.0036 square inch. Preferably, the open portion is circular having a diameter greater than {fraction (1/16)} inch, typically from xe2x85x9 to xc2xc inch. The nurse inserts the needle through this enlarged open portion when accessing the implanted medical device. Preferably, the enlarged open portion is about midway between the forward edge and the bite of the slot. Preferably, there are indicia on the guard section which assist the nurse in aligning the guard section with the implanted medical device during accessing. For example, there may be a pair of marks on the guard disposed along the slot which are spaced apart a distance approximately equal to the width of the implanted medical device, typically from xc2xe to 1 xc2xd inch. Alternately, the indicia may be at least partially encompassing the enlarged open portion along the slot. For example, the indicia may be a circle with its center coincident with the center of the enlarged circular open portion.
The fifth feature is that the tool is designed to enable the nurse to keep his or her hand a safe distance away from the needle during removal of the needle from the implanted device. The tool typically has a length of from 3 to 11 inches, and the handle section typically has a length of from 3 to 8 inches. The handle section has an elongated depression therein extending lengthwise along this handle section into which the thumb is placed during use. This depression provides a lever platform to enhance manipulative control of the tool. Thus, even someone with poor finger dexterity may easily manipulate the tool of this invention. In the preferred embodiment of this invention, the handle section has a marker on it indicating that the hand of the nurse should be behind this marker. The marker is at a distance to position the hand of the nurse safely away from the point where the needle is inserted into the implanted medical device. This distance is at least 2.5 inches away from the end of the slot terminating at an internal portion of the guard section. The handle section may include an intermediate neck section, and the guard section is joined to the intermediate neck. The handle section and the intermediate neck are at an acute angle of from 0 to 20 degrees, and the intermediate neck section and the guard section are at an acute angle of from 10 to 40 degrees. There may be a receptacle member on the elongated body in which a needle extracted from the implanted device may be inserted.
The sixth feature is that a special tool is provided for assisting in the manual insertion of a needle into the implanted medical device of a predetermined width. This tool includes a handle section and a holder section, with the holder section having a pair of fork elements spaced apart a distance which is slightly greater than the width of the medical device. Typically, this distance is from about xc2xd inch to about 2 inch. The fork elements are of equal length, each having a length of from about 0.5 inch to about 3 inch. The holder section has a length of from 0.5 to 3 inches and the handle section has a length of from 3 to 8 inches. The longitudinal axis of the handle section bisects the holder section, with each fork element being equidistance from the longitudinal axis. The holder section has a smooth, generally planar underside surface, and the handle section has a marker thereon indicating that the hand of the nurse should be behind this marker.
The seventh feature is that the handle section and guard section may be detachable, enabling the guard section to be discarded after use and the handle section reused. There is a locking mechanism that engages the handle section upon inserting the handle section into a track on the guard section and a manually releasable element that upon being released allows the handle section to be detached from the guard section.
The eighth feature is that the underside of the guard section has a depression therein having a configuration substantially the same as the configuration of the medical device, so that when the guard section overlies the implanted medical device and is pressed against the implanted medical device, the skin of the patient and at least a portion of the medical device are received in the depression. Preferably, the depression is a concave section. Advantageously, the guard section has a substantially circular configuration with an area of 1.0 square inch, which is slightly larger than the area of the top portion of the implanted medical device. The area may, however, be greater than 1.0 square inches. Preferably, the concave section has a center coincident with the center of the guard section and a substantially circular rim with a diameter of from {fraction (1/16)} to xc2xd inch, and a depth at the center of the concave section from {fraction (1/16)} to {fraction (3/16)} inch. In the preferred embodiment, the handle section and the guard section are molded from a polymeric material as a unitary structure, and the elongated slot extends radially outward from the center of the concave section to a circumferential edge of the guard section. The handle section has top wall and side walls extending from the top wall substantially at a right angle with respect to the top wall, and the marker comprises a raised portion on the top wall that serves as a thumb lever.
The ninth feature of this invention is that the handle has a connector section that is attached to the guard section, forming between this connector section and guard section an angle of 60 degrees or more, preferably between about 60 and about 90 degrees. This assists in maintaining the thumb a safe distance from the needle and creating a downward force applied to the guard section during use of the thumb lever.
This invention also includes a number of methods for accessing and deaccessing the implanted medical device. The first method is for manually removing a needle from a medical device implanted under the skin of a patient. It includes the following steps:
(a) grasping with the one, typically the non-dominant, hand a handle section of a tool having a guard section having an area of 1.00 square inch or more and a slot therein,
(b) sliding the slot along the needle to bring the guard section into an overlying relationship with the implanted medical device,
(c) maintaining the one hand a minimum distance away from the needle of at least 2.5 inches and exerting sufficient pressure to stabilize the guard area holding the implanted medical device preventing said device from moving,
(d) with the other, typically the dominant hand, withdrawing the needle free of the implanted medical device.
The deaccessing tool discussed above is used in performing this method.
The second method is for manually inserting a needle into a medical device implanted under the skin of a patient. It includes the following steps:
(a) grasping with one hand, typically the non-dominant hand, a tool with a holder section and a handle section, and holding a tool by the handle section and pressing the holder section against the skin overlying the medical device, and
(b) gripping the needle with the other hand, typically the dominant hand, and inserting said needle through said skin into the medical device, and
(c) maintaining said one hand a distance of at least 2.5 inches away from the needle as said needle is inserted into the medical device.
Either the tool discussed above which is designed especially for accessing the implanted medical device or the tool for deaccessing the needle may be used to conduct the second method. It is preferable that the guard sections of these tools be transparent and have indicia thereon which assist the nurse aligning the slot with the implanted device. These tools with transparent guard sections and indicia thereon may be used for both accessing and deaccessing the needle.